2021/07/08 (Thursday)
- Lab in-personnel: Pramod, Matt
| Status | Run 74 in progress. First cooldown after IVC rebuild. |
|---|---|
| Tower thermometer is reading high, probably this is a thermometer problem and the actual temperature is much lower. High noise in some of the charge channels. | |
| Setup: DIB1/2+acc → SL 41/43 → 3.2 MHz filters → cables 2/3 → nothing/Source_mover_board+HV_diverter_board → DCRC50(3)/55(1). Kepco 40V supplye → HV BNC. No lead/poly shield. (Currently DCRCs on, source mover board not plugged in) | |
| 0905 | Flash detector for 30 seconds with DCRC1&3 LEDs. Tower peaked at 0.32 K. |
| 1128 | Tower/MC/Coldplate = 79.4/33.16 /195 mK, Still = 1.43 K / 0.075 mbar / 0 mW, G1/G2= 246.7/226.2 mbar, 1K Pot = 1.624 K / 20±2 mbar. MB = 65.1% |
| 1140 | Fill LN2 cold trap bath. |
| 1200 | Do mvNwait +4steps×199times, 40 second wait, with dwell = 40 and power = 6.8 V. (Around 5.93 mm/hour.) After 18 minutes MC temperature peaked at 177 mK, then over the next 37 minutes it settled downward to an average of 172 mK and stayed there for the full sequence, ending at 2:15 pm. Condenser pressure increase from 240 to 275 mbar and stayed there for the rest of the sequence. |
| This move was a total of 13.12 mm. We are either right at detector center (y = 0.00 mm) or, if we were actually at the far endstop this morning, we are at y = -28.16 mm. This would be in q3 territory, first ring out from center, rather than q4. | |
| 1455 | Tower/MC = 220/36.5 mK and cooling. |
| 1510 | Plug in Cable 3 to DCRC1, look at noise. Adjust the DSub connections a bit (tightening and loosening one side or the other) until DCRC1qI noise drops by an order of magnitude to below 1e-5 at 10kHz |
| 1515 | At 10kHz noise in DCRC3qI/qO/DCRC1qI/qO = 2.8/1.1/4.5/3.3 e-6. This is q3/q1/q4/q2 At 3kHz (peak) noise in DCRC3qI/qO/DCRC1qI/qO = 24/5.5/6.1/30 e-6 |
| 1527 | Start 2 min series of 0V/-15V Start sequence with Start button. |
| Series aborted because DCRC3 channels triggering constantly… | |
| 1537 | Start 11 min series of 0V/-15V (bias applied after 80 seconds), with 1000 beginning randoms, trigger threshold 50/35/140/50 on DCRC3qI/qO/DCRC1qI/qO, 5Hz in-run randoms, with 1.6384 ms pulses (8192 length) and 400 us prepulse (500 length). Start sequence with Start button. |
| After applying bias we didn't see pulses, so I adjust the cables - then we saw a bunch of noise pulses, then it started triggering normally. | |
| crap!! data is not being written. abort series | |
| actually data was being written but not being copied to the /byseries directory. LazyLogger is maybe running too slow or something. Actually - lazylogger isn't runnning. After we finish this series we should restart MIDAS, then lazylogger should copy the data from /livedata to /byseries | |
| 1548 | Restart data series, same configuration as above. Run for 33 min |
| 1621 | Stop data series, dial bias to 0V. |
| 1625 | Flash detector for 30 seconds |